Comparison of Corticotomy and Micro-osteoperforation during Canine Retraction: A Split-Mouth Design.

OBJECTIVE: Compare the efficacy of the micro-osteoperforation (MOP) and corticotomy techniques in terms of maxillary canine retraction. METHODS: Thirteen patients (5 females, 8 males; mean age, 18.07 ± 6.74 years) with healthy permanent dentition and requiring the extraction of maxillary first premolars were included in a split-mouth randomized clinical trial. Those subjects with previous orthodontic or endodontic treatment of the canines were excluded. At least 3 months post-extraction, MOPs and corticotomies were performed distal to the canines. Mini-screws with closed-coil springs (150 g) were used for the canine retraction. Dental casts were made at baseline (T0) and 3 months post-intervention (T1). Trained and calibrated examiners measured the distances from the canines to the second premolars on both sides. A signed-rank sum test was used to compare the amount of canine retraction achieved in 3 months (T0-T1) on the 2 sides. RESULTS: Retraction (mm) at the incisal level was similar in the corticotomy (3.34 ± 1.01) and MOP patients (2.74 ± 1.10) (P = 0.11); furthermore, there were no differences in the degree of medial retraction between the corticotomy (2.56 ± 0.67) and MOP (2.27 ± 0.82) (P = 0.31) procedures. No adverse events were observed. CONCLUSION: There were not any clinically or statistically significant differences in retraction between the interventions. At 3 months, a MOP is as effective as a corticotomy in accelerating the rate of tooth movement.

Platelet-rich plasma's (PRP) impacts on accelerated canine movement.

OBJECTIVE: To investigate the impact of platelet-rich plasma (PRP) on canine movement acceleration. METHODS: Randomized clinical trial split-mouth study with a double-blind design and controlled group on 31 orthodontic patients, which had been indicated bilateral maxillary first premolar extraction. Each patient recorded clinical features, analyzed lateral cephalometric film, and evaluated the acceleration on dental models at every specific interval. RESULT: The cumulative distance to the distal canines was larger for the PRP injection group than for the control group at three time points (4 weeks, 8 weeks, and 12 weeks), all of which were statistically significant. The PRP injection group's canine distal width increased from the first 4 weeks (ΔT1) to the highest in the middle 4 weeks (ΔT2 = 1.78 ± 0.11 mm/month), and then it gradually decreased in the last 4 weeks (ΔT3). The speed of the PRP-injected canine was faster than the control group by 1.51 times. CONCLUSION: PRP can accelerate the speed of canine movement in orthodontics and can be applied for severe cases, for example, impacted tooth retraction, molar protraction or retraction, and other cases.

Evaluation of Patient-Centered Outcomes Associated With the Acceleration of en-Masse Retraction of Upper Anterior Teeth Assisted by Flapless Corticotomy Compared to Traditional Corticotomy: A Two-Arm Randomized Controlled Trial.

OBJECTIVE: This study aimed to assess the levels of pain, discomfort, and functional impairment associated with the en-masse retraction of the upper anterior teeth when treating Class II division 1 malocclusion patients using traditional corticotomy or flapless corticotomy. In addition, an assessment of patients' satisfaction with the selected surgical intervention was undertaken at one-month post-operatively. MATERIALS AND METHODS: The study sample comprised 40 patients with Class II division 1 malocclusion, randomly assigned to either the traditional corticotomy group (n=20) or the flapless corticotomy group (n=20). Patients underwent extraction of the maxillary first premolars, and orthodontic mini-screws were placed between the maxillary second premolars and the first molars for skeletal anchorage. An en-masse retraction was accomplished in both groups. Patients were asked to fill in a questionnaire at 24 hours (T1), four days (T2), seven days (T3), 14 days (T4), and 28 days (T5) after the surgical intervention using standardized questionnaires. Most questions were answered on a visual analog scale where zero scores meant the absence of pain, discomfort, or functional impairment, and 100 scores meant the worst feelings of these traits. RESULTS: All patients in both groups entered data analysis with no dropouts. All measured levels were significantly greater in the traditional corticotomy group during the first two weeks following the corticotomy intervention in terms of pain perception (P˂0.001), discomfort (P=0.004), and difficulty in chewing (P=0.015). Additionally, during the first week following corticotomy, levels of perception of discomfort (P˂0.001), difficulty in swallowing (P=0.001), and limitation of jaw movement (P˂0.001) were significantly greater in the traditional corticotomy group. Patient satisfaction, the recommendation to a friend, and acceptance of flapless corticotomy were significantly greater than traditional corticotomy (P=0.002, P=0.001, respectively). 78% of patients in the traditional corticotomy group considered it more discomfort than a tooth extraction, while 50% of patients in the flapless corticotomy group considered tooth extraction more discomfort, with a significant difference between the two groups (P=0.001). CONCLUSIONS: The levels of negative patients' reported outcomes were significantly smaller with flapless corticotomy than with traditional corticotomy. Traditional corticotomy was associated with mild to moderate levels of pain, swallowing difficulty, moderate levels of discomfort, chewing difficulty, and jaw movement limitation after 24 hours of the surgical procedure. In contrast, flapless corticotomy was less problematic and associated with mild pain, swelling, chewing difficulty, jaw movement limitation, and swallowing difficulty at the same assessment time. Patient satisfaction, acceptance, and recommendation to a friend were greater for flapless corticotomy than traditional intervention.

Effect of piezoincision on the rate of mandibular molar mesialization: A randomised clinical trial.

Background and Aim: The aim of this clinic study was to investigate the effect of piezoincision on the rate of mandibular molar mesialization using clinical, radiological, and biochemical methods. Materials and Methods: Twenty-one patients requiring mandibular first molar extraction and second molar mesialization were included in the study which was designed as split-mouth study. Piezoincision was performed on the buccal surface of alveolar bone following regional alignment to the randomly selected side. 150 g of force was applied to the second molar teeth using mini-screw-supported anchorage after the piezoincision. Cone beam computed tomography (CBCT), gingival crevicular fluid (GCF) and digital model records of the patients were obtained. Two- and three-dimensional measurements were performed and compared on the CBCT images in a study which lasted 24 weeks. Results: According to the model analysis, the canine-second molar distance was consistently reduced and a greater decrease was measured on the experimental group (p < 0.05). Second molar mesial rotations increased in both groups (p < 0.001). Two-dimensional measurements on CBCT images showed increased mesial and buccal tipping of second molars in experimental group (p < 0.001). There was a significant increase in mesialization measurements of experimental group (p < 0.001). Three-dimensional measurements on the CBCT images showed a decrease of root length in both groups (p < 0.001), and a greater decrease was found in the experimental group (p < 0.001). When intra-group changes in GCF results were examined, it was observed that there was no significant change in osteoprotegerin (OPG) values over time in experimental group (p = 0.148). Conclusion: The piezoincision technique provided acceleration of mandibular molar mesialization and did not cause further damage to the buccal alveolar bone. Piezoincision can be used as a safe method in the mandibular molar region.

Randomized clinical trial on the effect of intermittent vibrational force application during orthodontic treatment with aligners on RANKL and OPG concentrations in crevicular fluid.

Application of intermittent forces by vibration is proposed as an easy-to-use accelerator of dental movement. The purpose of this study was to determine the effect of intermittent vibrational force application during orthodontic aligner treatment on receptor activator of nuclear factor-kappa B ligand (RANKL) and osteoprotegerin (OPG) concentrations in crevicular fluid as markers of bone remodeling. This three-arm parallel randomized clinical trial included 45 candidates for malocclusion treatment with aligners, randomly assigned to: Group A (vibrational forces from onset of treatment); Group B (vibrational forces at 6 weeks after treatment onset); or Group C (no vibration). The frequency of aligner adjustment also differed among groups. At different time points, a paper tip was used to draw crevicular fluid samples from a moving lower incisor for RANKL and OPG analysis using ELISA kits. Mixed-model ANOVA found no significant differences in RANKL (A: p = 0.31, B: p = 0.8, C: p = 0.49) or OPG (A: p = 0.24, B: p = 0.58, C: p = 0.59) over time in any group or as a function of the application/non-application of vibration or the frequency of aligner adjustments. Application of this accelerator device did not significantly affect bone remodeling in patients undergoing orthodontic treatment with aligners. However, a nonsignificant improvement in biomarker concentrations was observed when aligners were changed every 7 days and vibration was also applied. Further research is warranted to establish protocols for the application of vibration and the timing of aligner adjustments.

Comparison of Maxillary Canine Retraction Using Split-Mouth Design With Dual Force Cuspid Retractor and T-loop Segmental Arch: A Split-Mouth Randomized Clinical Trial.

Introduction This study was designed to explore the differences between two frictionless mechanics for canine retraction i.e., dual force cuspid retractor and T-loop segmental arch. T-loop for canine retraction creates a biomechanical system to deliver a predetermined force and a relatively constant moment-to-force ratio whereas dual force cuspid retractor uses power arms on buccal as well as palatal aspects for canine retraction. Bodily tooth movement can be achieved by both methods, but in this study, our main focus was to reduce the canine retraction timing with better three-dimensional control. Method This split-mouth study was conducted on a total of 20 cuspids of ten patients (five male and five female). Where one side of the arch was selected for T-loop and the other side for dual force cuspid retractor, randomly. Inclusion criteria for this study were; no congenitally missing teeth (excluding third molar), class I or class II molar relationship, no previous history of orthodontic treatment, good oral periodontal status, patients in whom extraction of maxillary first premolar during treatment was indicated. Both groups were compared for the duration of canine retraction, anchorage loss; tipping, and rotation of cuspid and molar, individually, after retraction. Result The result of this study showed that the duration of canine retraction was significantly less in group one, i.e., dual force cuspid retractor 73.8 ± 12.38 days, than in group two, i.e., T-loop 109.4 ± 16.71 days. The anchorage loss in group one was 0.60 ± 0.61 mm and that in group two was 2.40 ± 0.87 mm. Also, the amount of tipping and rotation of the cuspid and molar individually was significantly lesser in group one than in group two. Conclusion In this study, the dual force cuspid retractor shortens the duration of canine retraction with better three-dimensional control and better anchorage preservation when compared to T-loop.

Effect of light-emitting photobiomodulation therapy on the rate of orthodontic tooth movement : A randomized controlled clinical trial.

PURPOSE: The aim of this study was to evaluate the effect of light-emitting photobiomodulation therapy (LPT) on the rate of canine distalization. METHODS: This study was performed on 60 extraction spaces formed by extraction of the upper first premolars of 30 patients (15 in the LPT group and 15 in the control group). Paul Gjessing (PG)-segmented canine retraction springs were used for canine distalization. In the LPT group, the Biolux OrthoPulse™ (Biolux Research Ltd, Vancouver, Canada) intraoral device (wavelength 850 nm LED light and an energy density of 63 mW/cm2 [±13 mW/cm2]) was used for 5 min per day over a period of 84 days. For each patient, the diagnosis was based on standard orthodontic documentation with photographs, digital model casts, and cephalometric and panoramic radiographs. The anchorage loss, canine rotations, canine inclinations, and molar inclinations were also evaluated on plaster models obtained on days 0, 21, 42, 63, and 84. The models were measured by using 3Shape OrthoAnalyzer software (3Shape, Copenhagen, Denmark). Measurements were made by a researcher and a blinded clinician. For statistical comparison, a paired-samples t­test and one-way analysis of variance (ANOVA) were used at the p < 0.05 level. RESULTS: The mean canine distalization rates were 1.36 mm/21 days and 1.02 mm/21 days in the LPT and control groups, respectively, and were statistically greater in the LPT group (p < 0.001). The amount of anchorage loss, canine rotations, canine inclinations and molar inclinations were not significantly different between the LPT and control groups at any of the timepoints. CONCLUSION: LPT has the potential to accelerate orthodontic tooth movement by 33%.

Adverse Effects of Surgically Accelerated Orthodontic Techniques: A Systematic Review.

Evidence on the potential adverse effects of surgically accelerated orthodontic techniques is scarce. The aim of this review was to evaluate the available scientific evidence regarding the adverse effects on periodontium, tooth vitality, and root resorption, associated with these surgical procedures in children, adolescents, and adults. The reporting of this review was based on the PRISMA2020 guidelines. Seven databases and three registers were searched for randomized clinical trials (RCTs) and controlled clinical trials (CCTs) published up to 22 June 2022. Hand searching of the reference lists of the included studies was also performed. The quality of the evidence was assessed with the Cochrane risk of bias and ROBINS-I tools. A total of 887 records were initially screened. Finally, 33 RCTs (713 patients), six CCTs (103 patients), and six ongoing protocols were eligible for this systematic review. The current review indicated that there are no significant adverse effects of surgically accelerated orthodontic techniques on periodontium, root length, or tooth vitality. High-quality clinical trials with less risk of bias should be conducted to allow reliable conclusions regarding the adverse effects of the surgical procedures associated with the acceleration of orthodontic treatment on children, adolescents, and adults.

Effects of vibrations induced by electric tooth brush on amount of canine retraction: A cross sectional study done at University of Lahore.

OBJECTIVE: To evaluate the effect of localized vibration on amount of canine retraction after 1st premolar extractions and to assess the anchorage loss. Methods: This quasi-experimental clinical study was conducted at University College of dentistry, Department of Orthodontics, University of Lahore. Data was collected from 30 patients who were already undergoing orthodontic treatment after taking their consent. The study was completed in one year, from Jan 2019 to Feb 2020. Results were compared with independent samples t-test using IBM-SPSS version 23.0. RESULTS: There was no statistically significant difference in the amount of tooth movement between the experimental and control side (p= 0.22). There was also no significant difference in the loss of anchorage (in terms of mesial movement of molar and rotation of canine) between both the groups (p > 0.05). Patients reported the use of electric tooth brush very practical and comfortable. No harm was observed. Conclusion: Supplemental vibrations induced by electric tooth brush did not increase the amount of tooth movement in terms of canine retraction nor did it decrease the loss of anchorage.

Effect of Extending Corticotomy Depth to Trabecular Bone on Accelerating Orthodontic Tooth Movement in Rats.

Corticotomy is a surgical procedure that induces injury to the cortical bone to accelerate tooth movement. This study aimed to increase the depth of corticotomy to the trabecular bone and to evaluate the amount and rate of tooth movement and alveolar bone changes in response to various degrees of cortical and trabecular bone injury. Seventy-eight male Wistar rats were randomly divided into four groups based on procedure used: (1) baseline control group of orthodontic tooth movement (OTM) only; (2) OTM + 4 corticotomies (CO); (3) OTM + 4 osteotomies (OS); and (4) OTM + 16 CO. A closed-coil nickel-titanium spring was placed to move the maxillary first molar mesially with a 10 g force. On days 0, 7, 14, and 21, alveolar bone alteration and tooth movement were measured using microcomputed tomography. Significant tooth movement was related to the number and the depth of the perforations. The OTM + 16 CO group showed a greater amount and rate of tooth movement than the OTM + 4 CO group. When osteotomy and corticotomy were compared with the same volume of bone removed, the OTM + 4 OS group had a faster rate of tooth movement than the OTM + 16 CO group during the first week, with significantly reduced bone volume. However, no significant difference was observed in the amount of tooth movement between the OTM + 4 OS and OTM + 16 CO groups at the end of the study. Extending the depth of corticotomy to trabecular bone increased the amount of tooth movement by accelerating the induction and completion of bone remodeling, which accelerated the rate of tooth movement during the initial stage.

Effect of micro-osteoperforations (MOPs) on the rate of en masse orthodontic tooth retraction : A randomized controlled trial.

PURPOSE: To evaluate the effect of micro-osteoperforations (MOPs) on the rate of orthodontic tooth movement (OTM) during en masse anterior retraction. MATERIALS AND METHODS: Twenty patients were randomly allocated into experimental and control group of 10 each. In the control group, en masse retraction was performed with sliding mechanics with a coil spring. In the experimental group after alignment and levelling, MOPs were performed mesially and distally to all six anterior teeth in the interdental cortical region on the labial aspect of both arches. MOPs were performed at the beginning of space closure (T0) and 1 month after beginning of space closure (T1). En masse retraction was performed with sliding mechanics with a coil spring. Measurements were recorded on digital models made from scanned plaster casts at the beginning of space closure (T0) and monthly at each follow-up visit for the next 4 months (T1, T2, T3, T4). The monthly rate of OTM, the overall rate of OTM, and the difference between OTM in the MOP period (T0-T2) and post-MOP (T2-T4) period in the experimental and control group were evaluated. A visual analogue scale (VAS) was used to evaluate patients' pain experience. RESULTS: The overall rate of OTM was significantly greater in the experimental group for both arches in the MOP period (T0-T2) and also in the post-MOP period (T2-T4) as compared to the control group. Within the experimental group, the rate of OTM in the MOP period was significantly greater than in the post-MOP period, which in turn was greater than that of the control group. The patients reported only mild discomfort for 24 h after performing the MOPs, which then gradually decreased. CONCLUSIONS: The use of MOPs is effective in increasing the rate of en masse tooth retraction in both the maxillary and the mandibular arch. The rate of tooth movement was greater even in the post-MOP period as compared to the control group.

Evaluation of the Effectiveness of Surgical Interventions Versus Non-surgical Ones When Used in Conjunction With Fixed Appliances to Accelerate Orthodontic Tooth Movement: A Systematic Review.

The objectives of this review were to evaluate the currently available evidence regarding the effectiveness of surgical versus non-surgical acceleration methods and the side effects associated with these methods. Nine databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL), EMBASE®, Scopus®, PubMed®, Web of Science™, Google™ Scholar, Trip, OpenGrey, and PQDT OPEN from pro-Quest®. ClinicalTrials.gov and the International Clinical Trials Registry Platform Search Portal (ICTRP) were screened to explore ongoing studies and unpublished literature. Randomized controlled trials (RCTs), as well as controlled clinical trials (CCTs) of patients who received surgical interventions (invasive or minimally invasive techniques) in conjunction with traditional fixed appliances and who were compared to the non-surgical interventions, were included. The Cochrane tool for risk of bias (RoB.2) was used for evaluating RCTs, whereas the ROBINS-I tool was used for the CCTs. This systematic review included four RCTs and two CCTs (154 patients). The surgical and non-surgical interventions were found to have the same effect on orthodontic tooth movement (OTM) accelerating in four trials. In contrast, the surgical interventions were superior in the other two studies. High heterogeneity among the included studies prevented conducting the quantitative synthesis of the findings. The reported side effects related to the surgical and non-surgical interventions were similar. A "very low" to "low" evidence indicates that the effectiveness of surgical and non-surgical interventions in the acceleration of orthodontic tooth movement is similar, with no differences in the associated side effects. More high-quality clinical trials to compare the acceleration effectiveness between both modalities in different types of malocclusion is required.

The Effectiveness of Periodontally Accelerated Osteogenic Orthodontics (PAOO) in Accelerating Tooth Movement and Supporting Alveolar Bone Thickness During Orthodontic Treatment: A Systematic Review.

The current review aimed to critically and systematically evaluate the available evidence regarding the effectiveness of periodontally accelerated osteogenic orthodontics (PAOO) in accelerating orthodontic tooth movement and supporting the alveolar bone. Additionally, this review aimed to analyze the untoward effects of this procedure and the patient-reported outcome measures. A comprehensive electronic search was performed on 10 databases in addition to a manual search to retrieve all relevant studies. Randomized controlled trials (RCTs) were only included in this review. The interventional group was the PAOO procedure, whereas the control group was either a non-accelerated traditional fixed orthodontic treatment or an accelerated treatment using any other intervention. The Cochrane risk of bias tool for randomized controlled trials (RoB 2) was employed to estimate the risk of bias in the included studies. The current review included eight RCTs evaluating 175 participants (63 males and 112 females) with a mean age ranging from 18.8 to 29.6 years. Five of them assessed the effectiveness of PAOO versus traditional orthodontic treatment, i.e. without any adjuvant surgical intervention. At the same time, the remaining three studies evaluated the effectiveness of PAOO versus corticotomy-only as an adjunctive procedure. The PAOO accelerated the leveling and alignment stage from 39% to 47% and accelerated the retraction of the upper anterior teeth from 41% to 61% compared to conventional orthodontic treatment. One study only indicated that PAOO reduced treatment time by 30.3% versus a corticotomy-only as an adjunctive procedure. No significant side effects have been reported with the PAOO procedure. The PAOO procedure was effective in accelerating orthodontic movement and tended to increase the thickness of the alveolar bone. But most periodontal outcome measures regarding PAOO application were not comprehensively covered in the included trials.

Systematic Review: Is High-Energy Laser Therapy (HELT) With Flapless Corticotomy Effective in Accelerating Orthodontic Tooth Movement?

The objective of this review was to critically and systematically appraise the available evidence regarding the effectiveness of high-energy laser therapy (HELT) with flapless corticotomy in accelerating orthodontic tooth movement and the associated untoward effects. We searched eight databases electronically in August 2021: PubMed®, Medline®, Google Scholar, Cochrane Library, Scopus®, Web of Science™, Trip, and PQDT OPEN from ProQuest. Another search was done in the reference lists of the included studies. Randomized controlled trials (RCTs) were included in which patients had received fixed orthodontic treatment combined with HELT-assisted corticotomy in comparison with traditional orthodontic treatment. Cochrane's risk of bias (RoB2) tool was used to assess the risk of bias. Five RCTs and one CCT were included in this review (155 patients). The HELT-based corticotomy around the upper canines led to a greater canine retraction at the first and second months (P < 0.001). In the third month, no statistically significant differences were noticed. In one RCT focusing on incisor intrusion, the irradiated upper incisors showed a greater intrusion speed than that of the control group (4.587 mm in 59 days vs. 3.78 mm in 95.8 days, respectively). No significant side effects associated with the application of HELT were reported. According to the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) approach, the quality of evidence supporting these findings was low to moderate. Although the acceleration of tooth movement appeared to be significant at least in the first two months, there was low to moderate evidence concerning the efficacy of HELT-based flapless corticotomy in the acceleration of orthodontic tooth movement. There is a need for more well-conducted high-quality RCTs.

Comparative study of different distraction rates in separate retractions of canine: Randomized control trial.

Introduction: Orthodontic treatment typically lasts 18-24 months, but depending on the conditions, it can take a longer duration. In recent years, accelerated orthodontics has been the subject of extensive research to shorten the duration of treatment. In distraction osteogenesis (DO), the surgically created joints are slowly and controllably displaced over time by gradual traction. This results in simultaneous growth of soft tissues and bone volumes at the osteotomy site. The DO field is currently experiencing a modern surge of research and development that has been able to implement numerous innovative and revolutionary distraction systems. In this study, we are comparing two different rates of dentoalveolar distraction. Materials and Methods: With the use of custom-made distractors, we will compare the different ranges of activation of distractors and their dental effects. Participants are separated into two groups based on 0.4 mm/day activation and 0.5 mm/day activation. Results: During the study period, the average tooth movement rate for Group 1 was 0.52 mm and for Group 2 was 0.58 mm. Group 1 completed canine distraction in 11.42 ± 1.81 days and Group 2 in 10.05 ± 1.68 days. Conclusions: Retraction days decreased in Group 2, due to increased activation of the distractor. The anchorage loss in Group 2 was higher than that in Group 1, which was 1.39 mm lower. Unlike decreased activation, the mean tooth movement of Group 1 is higher than Group 2.

Three-dimensional assessment of accelerating orthodontic tooth movement-micro-osteoperforations vs piezocision: A randomized, parallel-group and split-mouth controlled clinical trial.

OBJECTIVE: To compare the effects of micro-osteoperforations (MOPs) vs piezocision (Piezo) in accelerating orthodontic tooth movement in adults. SETTING AND SAMPLE POPULATION: In this randomized, single-blinded, parallel-group, split-mouth clinical trial, 24 patients aged 15-40 years were recruited. SUBJECTS AND METHODS: Patients were randomly allocated into two groups: MOPs and Piezo groups. One side of the maxilla was allocated randomly for treatment with one of these techniques, and the other side was treated conventionally to act as a split-mouth control. The rate of canine retraction was evaluated up to 3 months by three-dimensional digital models using a conventional labial appliance. Root resorption and bone height were evaluated using cone beam computed tomography. RESULTS: The MOPs and Piezo groups showed a significantly higher rate of tooth movement after 3 months on the experimental sides than the control sides. However, the net movements in the MOPs and Piezo groups did not reveal a higher rate of tooth movement. Similarly, the overall net movement was -0.32 ± 1.14 and -0.55 ± 0.89 mm for MOPs and Piezo, respectively (P = .606). Regarding root resorption, the overall changes in intra- or intergroup comparisons were insignificant. Decreased canine palatal bone height was reported on the experimental side of the Piezo group (P = .015) after 3 months, but the overall changes were insignificant. CONCLUSIONS: The effect of MOPs and Piezo techniques in accelerating the orthodontic canine retraction was comparable to each other, and to the conventional methods. Neither technique caused root resorption or increased vertical bone loss.

Which method is more effective for accelerating canine distalization short term, low-level laser therapy or piezocision? A split-mouth study.

OBJECTIVES: This study evaluated and compared the effects of low-level laser therapy (LLLT) and piezocision on the amount of orthodontic tooth movement. MATERIALS AND METHODS: Forty maxillary canines from 20 patients (mean age, 16.35 ± 1.14 years) were evaluated in a split-mouth design study. Miniscrew-supported canine distalization was performed. Piezocision was applied in the right maxillary canine region, and the left maxillary canines were irradiated with a diode laser (940 nm, 5 J/cm2). LLLT was performed on day 0 and days 3, 7, 14, 21, and 28 after the start of canine distalization in the first 4­week period. Data were evaluated at baseline (T0) and after 4 (T1), 8 (T2), and 12 (T3) weeks. The amount of canine movement was determined from three-dimensional models, and the angulation of canines and first molars was analyzed based on lateral cephalograms. RESULTS: Intragroup and intergroup comparisons of canine distalization were performed for four different time intervals (T0-T1, T1-T2, T2-T3, T0-T3). The canine tooth movement in the T0-T1 period was significantly greater in the LLLT group compared to the piezocision group. No statistically significant differences were observed between the groups for the T1-T2, T2-T3, and T0-T3 periods. The amount of canine distalization in the T0-T1 period was significantly greater than that in the T1-T2 and T2-T3 periods in both groups. Tooth movement during the T1-T2 period was higher than that in the T2-T3 period in the LLLT group. Cephalometric evaluation revealed no statistically significant difference between the groups with respect to canine and first molar angulation. CONCLUSION: Although laser application seems more effective during the first 4­week period, considering the 12-week period, the effects of LLLT and piezocision on orthodontic tooth movement during canine distalization were similar.

Distribution of mandibular trabeculae bone volume fraction in relation to different MOP intervals for accelerating orthodontic tooth movement.

OBJECTIVES: To investigate the effect of micro-osteoperforation (MOP) on the horizontal and vertical distribution of mandibular trabeculae bone volume fraction in relation to different MOP intervals during canine retraction. MATERIALS AND METHODS: This single-center, single-blinded, prospective randomized split-mouth clinical trial included 30 healthy participants aged 18 years and older, randomized into three groups of different MOP intervals (4, 8, and 12-weekly). Cone beam computed tomography images were taken to assess the bone volume fraction (bone volume over total volume or BV/TV). RESULTS: BV/TV was significantly reduced (mean difference: 9.79%, standard deviation [SD]: 11.89%; 95% confidence interval [CI]: 4.77, 14.81%; P < .01) and canine retraction increased (mean difference: -1.25 mm/4 mo, SD: 0.79 mm; 95% CI: -1.59, -0.92 mm; P < .01) with MOP, compared to control sites. MOP significantly changed the vertical and horizontal patterns of trabeculae bone with lower values nearer to intervention sites. Only the 4-weekly MOP interval group showed significant decrease in BV/TV (mean difference: 14.73%, SD: 12.88%; 95% CI: 3.96, 25.50%; P = .01) despite significant increase in canine retraction rate for all interval groups. With the use of MOP, BV/TV was found to be inversely correlated to the rate of canine retraction (r = -0.425; P = .04). CONCLUSIONS: Mandibular trabecular alveolar bone volume fraction was reduced and rate of orthodontic tooth movement increased with MOP, especially in the 4-weekly interval. However, this effect was limited to the immediate interdental region of MOP.

Vibration synergistically enhances IL-1ß and TNF-α in compressed human periodontal ligament cells in the frequency-dependent manner.

OBJECTIVES: To investigate whether mechanical vibration at 30 or 60 Hz combined with compressive force alter IL-1ß and TNF-α expression in human periodontal ligament (hPDL) cells. METHODS: hPDL cells isolated from the roots of first premolar teeth extracted from four independent donors were cultured and exposed to vibration (0.3 g, 20 min per cycle, every 24 h for 3 cycles) at 30 or 60 Hz (V30 or V60), 2.0 g/cm2 compressive force for 2 days (CF), or a combination of compressive force and vibration at 30 Hz or 60 Hz (V30CF or V60CF). Quantitative real-time polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assays (ELISAs) were used to determine IL-1ß and TNF-α mRNA and protein, respectively. RESULTS: The levels of IL-1ß and TNF-α did not alter in groups V30 and V60. While, they were upregulated in groups CF, V30CF and V60CF. In addition, IL-1ß mRNA and TNF-α mRNA and protein were expressed at significantly higher levels in group V30CF compared to CF group. However, IL-1ß protein levels between V30CF and CF groups did not reach statistical significance. CONCLUSIONS: 30 Hz vibration had the synergistic effects with compressive force on the upregulation of IL-1ß mRNA and TNF-α mRNA and protein in PDL cells, while 60 Hz vibration did not have this synergistic effect.

Evaluating the Efficacy of a Modified Piezo-Puncture Method on the Rate of Tooth Movement in Orthodontic Patients: A Clinical Study.

OBJECTIVE: Owing to the increasing demand from orthodontic patients for a more rapid treatment, many studies have focused on accelerated tooth movement. Currently, one of the prevalent methods to achieve accelerated tooth movement is piezo-puncture. The aim of the present study was to evaluate the effect of a modified piezo-puncture method on tooth movement rate and type during canine retraction. METHODS: A total of 17 patients who required fixed orthodontic treatment with extraction of the maxillary first premolars were included in the study. Following a split-mouth design, upper canines were retracted with Ni-Ti coil spring that applied 150 g of force on each side (piezo-puncture on one side and contralateral side served as the control). Then, the rates of tooth movement, canine angulation and rotation, and anchorage loss were evaluated at T0 (before the intervention), T1 (1 month after the intervention), and T2 (2 months after the intervention). For calculating the canine movement rate, either the distance between the canine and the lateral incisor or the space between the second premolar and the canine was measured. In addition, pain perception was documented by Visual Analog Scale. Data were analyzed using the Kolmogorov-Smirnov normality test, Spearman correlation test, paired sample t-test, and Wilcoxon signed-rank test. RESULTS: No significant acceleration was observed in canine movement, canine tipping, rotation, or anchorage loss of molar in different times. CONCLUSION: Considering the limitations of the study, the application of piezo-puncture employing the protocol used in the present study failed to accelerate tooth movement and to decrease the unfavorable tipping, rotation, and molar anchorage loss.